.nav {
  position: fixed;
  bottom: 0;
  width: 100%;
  height: 0.9rem;
  border-top: 1px solid #999;
  overflow: hidden;
  background-color: #fff;
  z-index: 999;
}
.nav a {
  position: relative;
  width: 20%;
  height: 100%;
  float: left;
  color: #999;
  text-align: center;
}
.nav a span {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  -webkit-transform: translate(-50%, -50%);
  width: .63rem;
  height: .85rem;
  background-image: url(../img/2016_9_30_10_24_37_8593_60x800.jpg);
  background-repeat: no-repeat;
  background-size: .63rem 8.5rem;
  overflow: hidden;
}
.nav a .nav-home-active {
  background-position: 0 .042rem;
}
.nav a .nav-search {
  background-position: 0 -0.85rem;
}
.nav a .nav-Tshirt {
  background-position: 0 -1.7rem;
}
.nav a .nav-shopcart {
  background-position: 0 -2.55rem;
}
.nav a .nav-me {
  background-position: 0 -3.4rem;
}
